haldi a petrochemicals limited haldi a

Haldia Petrochemicals Limited HALDIA, West Bengal

The 1052-acre petrochemical manufacturing site of Haldia Petrochemicals Limited (HPL) is located 110 kms south of Kolkata metro in the State of West Bengal on the bank of Haldi river. The site provides an easy access for bringing raw materials & dispatching finished product through river & sea as well as NH41 and lies in the hub of consumer intensive eastern region. HPL, a multi-product, fully integrated complex & producer of polyethylene / polypropylene plastics, liquid petrochemicals, & automotive fuels is the only such petrochemical manufacturer of eastern India. Manufacturing Facilities at HPL Naphtha is cracked at high temperature to produce ethylene and propylene. Pure products like Benzene, Cyclopentane and Butadiene are extracted from the cracked products. Ethylene is polymerized to LLDPE/HDPE in the polyethylene plants. Propylene is polymerized to PP in the polypropylene plant. Pyrolysis gasoline is hydrogenated & blended with other chemicals to produce Motor Spirit of EURO III quality. The complex has 116 MW captive power co generation plant based on naphtha. Oil jetties of Haldia dock are only 6 kilometer away & the plant is connected with the jetty through pipelines for the raw materials like Naphtha & Butene and for the products like Butadiene & Benzene. The complex operates on DCS. Planning the database for the business decision is governed by the use of the world class ERP-SAP system uniformly across HPL for capturing the data at source, for availability of information online, real time to the users for data security and for smooth data transfers interfaces. HPL naphtha cracking process is supported by process control simulation soft system of ABB, Lummus. HPL is the process of implementation of the Advance Process Control (APC), real time optimizer and IP-21 (Info plus) systems. Energy Consumption Drooping trend of energy consumption is the result of energy conservation efforts put-forth by HPL right from its inception. Data for the past four years is mentioned below.

Year (April-March)

Production (In Tons)

Electrical Energy KWH million

Qty per Unit Produced MM K

cal/MT

HDPE:202150 LLDPE:182380 PP:191800 Benzene:69000

65.1

89.7

49.2

1.09

12.2

0.41

0.26

0.30

0.80

3.96

2002 - 2003

Butadiene:17600


73.8

109

60.5

1.09

0.40

0.23

0.26

0.74

2003 - 2004

Butadiene:58000 14.0 1.84

2004 - 2005


78.2 102.0 60.3 1.08

19.77

0.42

0.24

0.25

0.72

1.66

Butadiene:68823

2005-2006


72.2 102.0 60.3 1.08

19.77

0.31

0.24

0.22

0.72

Butadiene:65479

1.65

Graphical Representation of Specific Energy Consumption(Mkcal/MT)

raphical Representation of Energy cost Vs Manufacturing cost

3000 3500 4000 4500 5000 5500 6000

Apr-03 Jun-03 Aug-03 Oct-03 Dec-03 Feb-04 Apr-04 Jun-04 Aug-04 Oct-04 Dec-04 Feb-05 Apr-05 Jun-05Aug-05 Oct-05 Dec-05

Month

Sp.Energy

0

20

40

60

80

100

120Cap. Utilisation

Energy, ActualEnergy, DesignCap. Utilin

G

Energy cost vs Mfg Cost , 2003-04

12% Energy

cost

RM & othercost

88%


9.6% Energy

cost

RM & othercost

90.4%


9.2% Energy

cost

RM & othercost

90.8%

Energy Management Policy Haldia Petrochemicals Limited is committed to superior energy management by adopting best practices through continuous improvement of knowledge, skills, processes and involvement of all employees and concerned business associates. S/D Managing Director Energy Management Set up HPL has three-tier energy management cell

EMAG

(Apex group of Top Management)

EMCG (Core group of Representatives

of each plant)

EMWG (Plant level working group)

Salient Features of Energy Management Set up The Energy Management Apex Group (EMAG) comprises of primarily the top

management at plant. The Plant-Head is heading this group, which comprises of all the HODs, General Managers, & Dy.General Managers. Sr.General Manager Technology who is the Energy Manager of the organization is the administrator of this EMAG.

Each of the plants & engineering discipline has a designated Energy Representative. The Energy Representative of Individual plant & Engineering discipline along with the representatives of Technology form the Energy Management Core Group (EMCG). Energy Manager is heading this group.

Energy Management Working Group (EMWG) is the initiative to involve shop floor people in the energy conservation. All the plants have nominated members for the EMWG and the training for the group was organized through PCRA. The groups have started regular meetings for brainstorming and developing ideas in their working area.

Activities of EMWG *Create & update data base for the Base level of energy consumption & finalizing Target * Monitor efficiencies of major energy consuming equipments * In-house Audit * Conceive & review new schemes * Implement approved schemes Activities of EMCG *Prioritize the new schemes. * Review & add value to schemes. * Guidelines to EMWG. * Energy accounting and MIS reporting to * EMAG & Statutory bodies. * Substitution of costly fuels. * Continuously creating awareness. * Planning for External Audit & Training. Activities of EMAG * Review Energy Cons. Trend. * Approve & Review implementation status of schemes. * Major decision making about Benchmarking. * External Training, External Audit, Appointing of external agencies etc. * Decision in implementation. * Review effort for improvement. * Guidelines to EMCG. Energy Conservation Achievements: Major Energy Conservation Schemes implemented

1. Using of nitrogen instead of fuel gas (FG) as sweeping gas for flare header Our original design was using of FG as the sweeping gas in the flare header. Original design consumptions of FG as sweeping gas were Sphere area: 300 kg/hr Loading gantry area: 30 kg/hr PP plant area: 75 kg/hr Flare stack: 600kg/hr i.e. total 1005 kg/hr of FG i.e. 8000 T per year of FG was suppose to be flared. By using of nitrogen as sweeping gas for flare header we are avoiding this flaring of FG. Thus saving of 12000 x 8000 x 1000 i.e.96000 MM Kcal energy in terms of FG.

2. Butadiene dispatch through jetty pipeline (Trend Setter Plant Modification :First time in the world to have Butadiene pipe line of 12 km length in total connecting plant to river port) Basis: 4000 T/month dispatch to Kandla as there is no ship loading facility for Butadiene at Haldia i.e 220 tankers /month Haldia to Kandla (to & fro of dedicated tankers): 2500 X 2 =5000 km Fuel consumption: 6km/lit of diesel Diesel consumption per tanker: 5000/6=830 lit Total anual diesel consumption will be 220 x 830 x 12 = 2191200 lit= 1862520 kg = 1862 T To avoid this road transport, HPL had put up a dedicated pipeline from HPL to Haldia Oil Jetty & started dispatches butadiene from Haldia directly. This saves 1862 T HSD on yearly basis i.e. saving of 1862 x 10500 x 1000 = 19500 MM- Kcal of energy in terms of HSD. 3. Cooling Tower (CT-I)fans design changed The original design of 8 blades FRP blade fans (9 No.s) had been replaced with 6 blades aerodynamically designed fans by which the consumption of electricity had been reduced from 85 KWH/Hr to 54 KWH/Hr per fan. Thus annual reduction of energy consumption of 223 MWH for 9 fans. 4. Butadiene chiller modification Butadiene is subject to oxidation & polymerization with increased temperature. Butadiene is therefore cooled in storage to maintain a temperature of 8-5c in sphere. For this, butadiene refrigeration system is provided to maintain the storage temperature & to offset any heat pick up during circulation in the pipeline. The system was put in to operation during commissioning in late 2000; since commissioning several problems have been encountered resulting poor chilling, thus higher run-hours of the compressor. Problem encountered: During the operation it has been noted that large quantity of liquid propylene getting accumulated in the Knock Out Drum (KOD) (being carried out from butadiene chiller) at full load of the compressor & even at the 50% loading of the compressor. Liquid level rapidly builds up in the KOD & the compressor got tripped at high level in KOD. To maintain the suction pressure, the pressure control valve got fully opened to put hot vapor in the KOD. Thus the full energy of the compressor is not utilized. To avoid liquid carry over from the chiller, minimum liquid level was maintained in the chiller. Thus most of the Butadiene tube bundles are not immersed in the liquid propylene. So chilling effect on Butadiene was nominal resulted continuous running of the compressor against the 16 hr running & 8 hr.s recession philosophy. Temperature across the chiller in butadiene was only 3c against the design of 5c. The problem could not be solved even after communication with the designer for several times. Root cause analysis: For proper disengagement of vapor from liquid internationally established design literature says, The distance from the centerline of the uppermost tube in a horizontal bundle to the top of the shell should not be less than 40% of the kettle dia. In our case this space was found to be only 28 % of the kettle dia. At the same time it was also found that the chiller does not have any demister to eliminate the liquid mist to carry over. These design defects were found to be the root causes of the problem. Proposed changes/modifications: It was proposed to provide a disengagement vessel (with built in demister) in between the chiller & the Suction KOD. The height of the vessel would be 300mm, which would act as the additional disengagement space. As the vessel would be with the demister this will

eliminate the possibility of any further liquid carry over to KOD. The vessel will have 1:15 slope so that the disengaged liquid will be drained down to the chiller. Benefit observed after modification:

No liquid carry over observed in the KOD. Butadiene differential temperature across the chiller improved from 3c to 6.5c. Compressor running hours reduced to ~ 6 hr/day i.e. the about 10 hrs reduction

of 250KW motor running on daily basis. Suction pressure control valve opening almost nil thus full compressor loads is

being utilized.

5. Mist Cooling System Haldia Petrochemicals Limited had adopted a unique new concept of cooling tower named Mist Cooling System of 12000 m3/hr for its revamp, which do not require any fan. A similar capacity conventional cooling tower would have been call for 4 no.s 90 KWH motor running for 8000 hr. Thus it saves energy 8000 x 4 x 90 = 2.8 MMKcal on annual basis.

Mist Cooling Pond & Spray nozzle. 6. Part replacement of naphtha with excess fuel gas in captive power plant In HPL plant initially, as per the original plant design, there was no provision for utilizing excess raw Fuel Gas (RFG) in the emergency stand by Auxiliary Boiler (AB) of Captive Power Plant (CPP). It was initially a difficult proposition for the power plant to partially substitute naphtha (main fuel for power plant) by consuming the excess RFG generated in house in AB due to the unreliability and variability of its supply. Also this partial replacement of naphtha by FG was subjected to technical plant modifications. However, considering the clean environmental development & non-realization of the LHV of excess RFG, HPL has taken up this project by ensuring raw Fuel Gas supply to CPP by the following process modification: In case there is any shortfall in the supply of FG, Propylene vapour from propylene sphere is sent to maintain the fuel gas header pressure for half an hour to aid a smooth change over from RFG to liquid fuel. This is helping to maintain the uninterrupted supply of RFG to AB during the station black out situation. The project case includes the following technical modifications: A new pressure control valve has been installed in the Propylene sphere BOG line, the down stream of which has been joined with the RFG distribution network so that whenever there is a short fall in the RFG header pressure, the newly installed control valve will open & Propylene BOG will let down in to RFG header. After this modification, during normal operation the emergency stand-by boiler ie. AB is on 100% RFG. During Station Blackout (SBO), RFG header pressure is being maintained by automatic let down of propylene vapor from sphere and keep on supplying about 8-9 TPH of RFG for CPP for a short period of about 30 minutes.

By reducing the consumption of naphtha through its partial substitution with excess RFG (which is otherwise flared) this project positively contributes to the diminishment of the total CO2 emission from the plant as well as utilization of LHV of excess FG & lowering of consumption of main liquid fuel, i.e. naphtha. This modification was implemented in April04 annual shut down. The attached trend curve shows the reduction of Liquid fuel (Naphtha) consumption in power plant from avg.14.9 T per hour before implementation to 13.5 T per hour & increase of RFG consumption from avg. 3.7 T per hour to 5.35 T per hour. Raw Fuel Gas(RFG) Utilization in CPP

18.8618.9918.6019.0419.118.819.1

15.35

18.3018.5319.10

15.3113.5114.3513.80

14.8313.8113.5413.8013.42

14.6914.79

3.79 3.74 3.61

1.93

5.30 5.24 5.284.64

5.354.804.21

0.00

5.00

10.00

15.00

20.00

25.00

Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 Jul-04 Aug-04 Sep-04 Oct-04 Nov-04

TPH

0.00

3.00

6.00

9.00

12.00

Total Fuel Consumption, TPH Other liquid Fuel, TPH RFG Consumption, TPH

7.Steam saving in side reboiler in depropaniser tower of NCU Depropanizer tower separates C3 and C4+ components and the depropanizer system employs two towers- Depropanizer 1(DP1) and Depropanizer 2 (DP2). DP1 and DP2 both distillation towers are having two reboilers. One is bottom steam reboiler where satd LP steam is used and other one is side reboiler where circulating quench water is used as heating medium. To recover low level heat from quench water and reducing steam consumption in main reboilers in both towers, side reboilers heat load are maximized and substantial steam saving is done in both towers. With this modification both towers operations are found normal. 8366 T/ Annum LP steam had been saved.

SIDE REBOILER in NCU 8.Steam Saving due to DP2 feed cooler CW throttling The Depropanizer system employs two towers (Depropanizer 1and Depropanizer 2) for separation of C3's and C4+ components. Depropanizer 1(DP1) is receiving feed from De-ethaniser bottom and Depropanizer 2 (DP2) is receiving two feeds; one is from DP1 bottom and another is from condensate stripper bottom. Feed from condensate stripper bottom is cooled by CW exchanger( 2E-321) before sending it to DP2. By throttling CW supply to cooler, feed temperature is increased from 40 deg C to 55 deg C and tower operation is found stable and normal. Steam comsumption in reboiler is reduced by 0.5 t/hr.

2E-321 in NCU 9. 2K-300 power saving due to higher suction pressure Cracked gas from heater area is compressed from 0.2268 kg/cm2g to 37.35 kg/cm2g in CG compressor (2K-300). SHP steam is used as motive steam to drive CG compressor turbine (2KST-300). Presently, we are operating CGC compressor at suction pressure of 0.55 kg/cm2g instead of 0.2268 kg/cm2g. Since suction pressure is on higher side and discharge pressure remains same, compression ratio for 5 stages will be less than design. Therefore, power consumption is less than design for compression of the same amount of gas and accordingly, steam consumption in 2KST-300 is less than design. The following calculation is done based on plant load @ 540 KTA. Total power saving is 16011771 KWH/annum due to high CG compressor suction pressure.

Cracked Gas Compressor 10.Power saving Due to low running hours of Decoke Compressor (2K-210) Naphtha cracker Unit at Haldia Petrochemicals Ltd is having 6 liquid naphtha cracking heaters and one recycle heater for cracking of ethane and propane generated in Naphtha Cracker Unit. After few days of heater operation, coke gets deposited inside cracking coils and to remove this coke, decoking is done using steam and air at high temperature. One decoke air compressor is provided in Naphtha Cracker Unit to supply decoke air when decoking of heater coils is there. During decoking of any heaters decoke air compressor is run for 8 hrs instead of 16 hrs for liquid heaters and for 16 hrs instead of 32 hrs in case of recycle heater. Decoke air for the first 8 hrs is received from IOP for liquid heaters decoking. For recycle heaters decoking decoke air for first 16 hrs is received from IOP. At IOP side no extra compressor is required to be run for this. Thus, 8 hrs power for 2K-210 compressor is saved for every decoke cycle for liquid heaters and 16 hrs power is saved in case of recycle heater decoking. Total power saving for this modification is 836941 KWH/annum

Decoke Air compressor Energy Conservation Plans and Targets The Target set for year 2005-06 by the company is - Reduction in specific power consumption by 1.5% minimum by March 2006 Reduction in steam specific consumption by 1.5% minimum by March 2006.

Major Plan for 2006-07

1. Replacement of six no.s of Cooling Tower fans of CT-II 2. APC optimization for Naphtha Cracker to optimize on line system based energy

consumption. 3. Improvement in steam condensate recovery. 4. Transfer of low polymer HDPE without pump. 5. Reduction in power consumption in Powder conveying system. 6. Stopping of one vacuum pump in Benzene plant. 7. Implementation of energy audit findings.

With all these plant modification we target the specific energy consumption reduction of about 1.5% within March 2007.

Energy conservation Measures 2005-2006

Measure

Power saving by changing design of fan blades of cooling tower1

Details of measure

The cooling tower (CT-1) has 9 cells. As per original design each cell was having FRP blade fan with 8 blades. These fans have been replaced with aerodynamically designed 6 blade fan. This has resulted in a power saving of 20.7 KWh per fan.

Technical & Financial impact of modification

Total no. of fans: 9

Total running hours per year: 8760

Power saving per fan : 20.7 KWh per fan.

Total KWh saved: 1631988 KWh

Unit rate of KWhL : 6.45 Rrs/KWh

Total savings: Rs 105.26 lakhs per annum.

Investment: Rs.31.5 lakh

Annual energy Savings:1631988 KwH

Actual savings: Rs 105.26 lakhs per annum

Payback: 4months

Implementation Highlights

EQUIPMENT

Blade Type

Blade Angle ason 16/01/05

Motor Rating

Amps with ModifiedENCON blades on Jan'05

Power Consumption in Watt with new Encon modified blades (1.4722*415*I)

Amps With Gammon makes Old Blade As on Avg of Feb'03 except Fan-B of July '02

Power Consumption in Watt with old Gammon make blades (1.4722*415*I)

Power Savings Watt

Average power saving per fan in KW

25-AXF-001A New 11 90Kw 80 48877.04 130 79425.19 30548.1525-AXF-001B New 11 70 42767.41 130 79425.19 36657.7825-AXF-001C New 11 90Kw 80 48877.04 120 73315.56 24438.5225-AXF-001D New 11 90Kw 100 61096.3 120 73315.56 12219.2625-AXF-001E New 11 90Kw 100 61096.3 120 73315.56 12219.2625-AXF-001F New 11 90Kw 80 48877.04 120 73315.56 24438.5225-AXF-001G New 11 90Kw 80 48877.04 105 64151.115 15274.07525-AXF-001H New 11 90Kw 70 42767.41 110 67205.93 24438.5225-AXF-002F New 11 75Kw 90 54986.67 100 61096.3 6109.63

20.7048572

Energy Conservation Measures 2005-2006

Measure

Utilisation of excess fuel gas from Naphtha Cracker plant (NCU) in Captive Power plant CPP)

Details of measure

Naphtha Cracker Unit generates fuel gas along with main products ethylene and propylene. This fuel gas is mainly used in heater operation in Naphtha Cracker operation and any extra fuel gas is supplied to CPP for maximum utilisation of fuel gas. Presently, Naphtha cracker unit is operated at 540 KTA Ethylene instead of 420 KTA (design) and consequently, fuel gas generation is also higher than design. Earlier, excess fuel was sent to flare from NCU plant. Presently, a new 6 line is installed to transport the excess Fuel Gas to CPP. In CPP, naphtha consumption is consequently reduced.


Extra FG supplied to CPP Tons/hr 0.5 Excess FG saved per annum T/annum 4000 Basis: FG calorific value Kcal/kg 12000 Fuel Gas price @Rs 30000/ton 25000 Total heat value Mkcal/Annum 48000 operating hours 8000 hrs/annum 8000 Equivalent Naphtha saved Tons/year 4571 Annual Savings Crores 12

Investment: Rs 4 lakhs

Annual energy Savings: 47995 M K Cal/ Annum

Actual savings: 12 crores

Payback: 1 day

Implementation Highlights: Excess fuel gas saved is 4000 ton/annum


Measure

Steam saving by increasing feed temperature to Depropanizer-2 column by throttling cooling water in 2E-321(Condensate stripper bottom Cooler)

Details of measure

The Depropanizer system employs two towers (Depropanizer 1and Depropanizer 2) for separation of C3's and C4+ components. Depropanizer 1(DP1) is receiving feed from De-ethaniser bottom and Depropanizer 2 (DP2) is receiving two feeds; one is from DP1 bottom and another is from condensate stripper bottom. Feed from condensate stripper bottom is cooled by Cooling water exchanger( 2E-321) before sending it to DP2. By throttling cooling water supply to cooler, feed temperature is increased from 40 deg C to 55 deg C and tower operation is found stable and normal. Low pressure steam consumption in reboiler is reduced by 0.5 t/hr.


Steam saving 0.5T0ns/hr Yearly steam saving 4000Tons/annum Energy saving 2677.81Mkcal/annum Steam enthalpy 2803KJ/kg 669.45Kcal/Kg Feed flow 34Tons/hr Sp, heat 0.7Kcal/Kg/degC Heat load 357000Kcal/hr 0.35Mkcal/Hr

Investment: NIL

Annual energy Savings: 2677.81m k Cal/Annum

Actual savings: Rs.80 lakh

Implementation Highlights: Low pressure steam saved is 4000 ton/annum


Measure

Steam saving by maximizing the loading of side reboilers in depropanizer towers of Naphtha Cracker plant

Details of measure

Depropanizer tower separates C3 and C4+ components and the depropanizer system employs two towers- Depropanizer 1(DP1) and Depropanizer 2 (DP2). Both DP1 and DP2 distillation towers

are having two reboilers. One is bottom steam reboiler where saturated LP steam is used and other one is side reboiler where circulating quench water is used as heating medium. To recover low level heat from quench water and reduce steam consumption in main reboilers in both towers, side reboilers heat load has been maximized and substantial steam saving is done in both towers. With this modification both towers operations are found normal.


Heat duty reduction

Reduction of heat duty in DPI steam reboiler 370794Kcal/hr

Reduction of heat duty in DP2 steam reboiler 168176Kcal/hr

Total reduction in heat duty in DP1&DP2 538970Kcal/hr Eqivalent LP steam(satd) 1067.487KG/hr

Enthalpy of LP steam (satd) 2746KJ/KG

Enthalpy of LP cond (satd) 632KJ/KG

steam(satd) saving/annum 8540Tons/annum

LP steam (superheated) saving 8366T/annum

Enthalpy of LP steam (superheated) 2803KJ/KG Investment: NIL

Annual energy Savings:12423 M K Cal

Actual savings: Rs.150 Lakh

Implementation Highlights: Low pressure steam saved is 8366 tons/annum


Measure

Stopping of DMDS dosing pump in Associated units plant.

Details of measure

DMDS had been dosed continuously into 4R-102 to maintain a specific quantity of H2S in hydrogen recycle gas. As Thiophene is present in sufficient quantity in feed to 4R-102 DMDS dosing is discontinued.So electical power is saved.


KW of 4P-116 2.2

Power saved in a year (KWH) 17600 Cost of power (Rs./KWH) 6.45

energy saved in terms of money (Rs.) 113520

Investment: NIL

Annual energy Savings: 17600 k Cal

Actual savings: Rs.113520

Implementation Highlights: power saving of 17600 KWh per annum


Improvement is steam condensate recovery system in polypropylene plant by modifying header and steam traps

Details of measure

In PP Plant the steam condensate generated from Flash loop jacket sytem is not fully recoverable due to recovery limitation. The two nos of condensate recovery sub headers merge into one header and goes into Condensate Recovery Vessel 9V-604. Then it is sent to IOP for recycle. The steam condensate recovery has been increased by 50 % (1.5 MT per hr) after modifying condensate line and its size, higher capacity steam traps and condensate header.The following major modification jobs have been performed to increase the recovery of steam condensate.

a)2 condensate header which collects condensate from the flash loop steam traps increased to 4 header.

b)2 condensate header for flash loop condensate at higher elevation had been rerouted to

separate header up to condensate recovery tank.

c) High capacity traps installation and relocation of steam traps in some places.

d) Line layout changing thereby reducing bends in condensate sub header to reduce back pressure.


Steam condensate saving 1.5 T/hr

Yearly condensate saving 13140 T/annum

Energy saving 1185.02 Mkcal/annum

Steam Condensate enthalpy 377.6 KJ/kg

90.18 Kcal/Kg Investment: Rs. 1.22 lakhs

Annual energy Savings: 1185 M K Cal

Actual savings: Rs.6.57 lakh

Payback: 6 months

Implementation Highlights: Condensate saving of 13140 tons/annum.


Measure

Purge gas recovery in Polypropylene plant during high rate of venting

Details of measure

The purge gas line from PP to NCU had been designed for a capacity of maximum 900 Kg per hr at an inlet pressure of 2.5 kg/cm2. The capacity requirement was 1600 kg per hour during Random Co Polymer (RCP) run. But the header had been unable to take the extra quantity to NCU due to higher back pressure generated in the off gas line (by other user plants). In PP Plant , other off gas generation lines from various sections were also connected in the same header. For stable reactor operation at higher capacity, process needs some inerts purging at a higher rate continuously. Hence purge gas quantity had to be increased during high amount of inert venting cases. Also during Gas phase reaction during impact copolymer production, more hydrocarbon purging had to be required to maintain stable gas composition in the reactor. The excess purged gas was flared during high rate of venting.The original design of the Purge gas header has been changed to recover the whole amount of off gas generated during different cases. To reduce the Off Gas line back pressure, the subheader (of other purge gas generation points) has been rerouted and the tie-in point has been shifted to the same header. The recovery amount has been found to be increased by 24 % by performing the modification as well the maximum capacity can be handled by the modification has been found to be 1760 kg per hour.


Purge gas recovery increased 0.228 T/hr

Yearly saving (Actual) 1974 T/annum

Energy saving 24675 Mkcal/annum

Calorific Value of Purge Gas 12500 Kcal/Kg

Investment: Rs 55000

Annual energy Savings: 24675 M Kcal

Actual savings: Rs.592 Lakh

Payback: Few hr.s

Implementation Highlights: Savings in purge gas flaring by 1974 tons/annum.


Measure

Power saving by reducing backpressure at extruder gear pump at High Density polyethylene plant

Details of measure

Extruders are used converting polymer powder to pellet. While passing through the Extruder, powder gets melted which is pumped to the die plate with the help of gear pump. In the downstream of die, molten polymer is cooled with water and cut in the pellet form by using a cutter unit. Die plate is having 1400 holes of 2.6 mm diameter to pass the molten polymer through it and it is having channel inside it, which is used for heating the die plate with the help of hot oil of 290C. In one of the Unit which has two lines for HDPE production, gear pump discharge pressure

Gear Pump

Water In

Cutter

Screen

Water +Pellet

Die Plate

was high and was a limitation to run the Extruder at high load, as well as energy consumed by this pump was high due to same reason. Measure: After checking the design consideration of die plate it was confirmed from the equipment vendor that increasing the die hole from 2.6 mm to 2.9 mm will not affect the strength of die plate . So die hole diameter was increased from 2.6 mm to 2.9 mm which resulted in lowering of gear pump discharge pressure by ~5% (310 kg/cm2 290 kg/cm2) and lowering of gear pump power consumption by 5~9%.

At the same time margin w.r.t. gear pump discharge pressure was achieved to run the Extruder in safe zone.


Gear Pump Details:

Pump Particulars Unit Details

Service - Molten Polymer Number of pumps No. 2

Number of pumps operated No. 2 Motor KW KW 700

Earlier power consumption by two pumps per hour: 795 KW Present power consumption by two gear pumps per hour: 743 KW Annual power saving: 416 MWH Annual cost savings: Rs 22.6 lakhs

Investment: 0.28 lakhs

Annual energy Savings: 416 MWH

Actual savings: Rs 26.83 lakhs

Payback: 5 days

Implementation Highlights:

Power saving by 416 MWH per annum

2 E-321 in NCU

Energy Saving done in 2005-06

DMDS PUMP Energy Saving done in 2005-06

SIDE REBOILER IN NCU


CHARGE GAS COMPRESSOR


DECOKE AIR COMPRESSOR IN NCU


Manufacturing Facilities at HPL Energy Consumption Graphical Representation of Specific Energy Consumption(Mkcal/MT) Graphical Representation of Energy cost Vs Manufacturing cost

Energy Management Set up Activities of EMWG Activities of EMCG

Our original design was using of FG as the sweeping gas in the flare header. Raw Fuel Gas(RFG) Utilization in CPP

7.Steam saving in side reboiler in depropaniser tower of NCU 8.Steam Saving due to DP2 feed cooler CW throttling 9. 2K-300 power saving due to higher suction pressure 10.Power saving Due to low running hours of Decoke Compressor (2K-210) Decoke Air compressor Energy Conservation Plans and Targets Major Plan for 2006-07 Energy conservation Measures 2005-2006 Energy Conservation Measures 2005-2006Energy Conservation Measures 2005-2006Energy Conservation Measures 2005-2006 Energy Conservation Measures 2005-2006 Energy Conservation Measures 2005-2006 Energy Conservation Measures 2005-2006 Energy Conservation Measures 2005-2006 Pump Particulars

2 E-321 in NCU DMDS PUMP Energy Saving done in 2005-06

SIDE REBOILER IN NCU CHARGE GAS COMPRESSOR DECOKE AIR COMPRESSOR IN NCU

haldi a petrochemicals limited haldi a

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